Weather & Roof Performance Data 2026

Savannah's Climate: A Stress Test for Every Roof

Savannah's subtropical climate is among the most demanding environments for roofing materials in the United States. The combination of extreme heat, persistent humidity, heavy rainfall, intense UV radiation, and occasional hurricane-force winds creates a multi-vector assault on every component of your roof system — from the shingles to the decking to the flashing.

At Talya Roofing, we don't just install roofs — we engineer them for the specific conditions that exist in Savannah, Pooler, Richmond Hill, Tybee Island, and across Chatham County. Understanding the climate data behind our material and installation choices helps homeowners appreciate why local expertise matters more than price alone.

Temperature Extremes and Thermal Cycling

Savannah's average high temperature in July and August reaches 92°F, with frequent spikes above 100°F. On a dark asphalt shingle roof, surface temperatures can exceed 160°F during peak sun exposure. At night, temperatures can drop 30–40 degrees, creating a daily thermal cycle that repeats from May through September.

How Thermal Cycling Damages Roofing Materials

• Expansion and contraction: Roofing materials expand when heated and contract when cooled. Over thousands of cycles, this movement loosens nails, stretches sealant strips, and creates micro-cracks in shingles.
• Asphalt binder degradation: The volatile oils in asphalt shingles evaporate faster at high temperatures. This is why shingles in Savannah lose flexibility and become brittle years earlier than identical shingles in cooler climates.
• Flashing fatigue: Metal flashing around chimneys, vents, and valleys expands and contracts at different rates than surrounding materials, eventually breaking the seal and allowing water penetration.
• Sealant failure: Self-sealing shingle strips rely on heat to activate, but excessive heat can cause over-softening followed by hardening, reducing their long-term adhesion.

For homeowners considering a roof replacement, choosing materials with enhanced thermal stability — such as SBS-modified shingles or metal roofing — significantly improves longevity in our climate.

Humidity and Moisture Cycling

Savannah's average relative humidity is 74%, with summer mornings frequently reaching 90% or higher before afternoon heating provides partial relief. This persistent moisture creates conditions that challenge roofing systems in ways most homeowners don't see until damage becomes visible.

The Moisture Cycling Effect

Moisture cycling occurs when roofing materials absorb moisture during humid periods and release it during dry or heated periods. Wood decking is particularly susceptible — it swells when wet and shrinks when dry, warping over time and creating an uneven surface that compromises shingle adhesion. In Coastal Georgia, this cycle happens daily during summer months.

• Plywood roof decking in Savannah degrades 15–20% faster than in drier climates due to moisture absorption.
• Moss, algae, and mildew growth thrives in our humidity, trapping moisture against shingle surfaces and accelerating granule loss.
• Attic condensation from humidity differentials can soak insulation and rot rafters from the inside out.
• Proper ventilation is critical — a well-ventilated attic reduces moisture buildup by 40–60%.

Rainfall Patterns and Water Management

Chatham County receives an average of 49.6 inches of rain per year, with the heaviest rainfall occurring between June and September. Tropical systems and afternoon thunderstorms can deliver 2–4 inches in a single hour, overwhelming gutters and drainage systems that work fine during moderate rain.

Rainfall Data for Savannah, GA

• Annual average: 49.6 inches (compared to the U.S. average of 38.7 inches)
• Wettest months: July (6.5"), August (7.1"), September (5.3")
• Average rain days per year: 106
• Maximum 24-hour rainfall (recent years): 8.2 inches during tropical events

This volume of water makes proper flashing, underlayment, and drainage design non-negotiable. A professional roof inspection should always evaluate water management systems — not just shingle condition.

UV Radiation: The Silent Roof Killer

Savannah receives approximately 2,500 hours of sunshine per year and sits at latitude 32°N, where UV intensity is significantly higher than in northern states. The UV index regularly reaches 10–11 during summer — classified as "very high" to "extreme" by the EPA.

Ultraviolet radiation is the primary cause of shingle aging. It breaks down the chemical bonds in asphalt binders, causing shingles to become brittle, curl, and lose the protective granules that shield the underlying material from further degradation. A roof that might last 30 years in Michigan may only last 20–22 years in Savannah under identical maintenance conditions.

UV-Resistant Material Options

• SBS-modified (rubberized) asphalt shingles resist UV cracking better than oxidized asphalt.
• Ceramic-coated metal roofing reflects UV radiation rather than absorbing it.
• Algae-resistant shingles with copper granules prevent the dark staining caused by Gloeocapsa magma, which also traps heat.
• Cool-colored shingles with higher solar reflectance index values reduce UV-related thermal degradation.

Seasonal Maintenance Scheduling for Coastal Georgia

Based on Savannah's distinct climate patterns, Talya Roofing recommends a seasonal maintenance approach that aligns inspections and preventive care with the weather events most likely to cause damage.

Spring (March–May): Post-Winter Assessment

After winter storms and temperature fluctuations, spring is ideal for a comprehensive roof inspection. Check for loose or damaged shingles from winter winds, inspect flashing around penetrations, clear debris from valleys and gutters, and ensure attic ventilation is functioning properly before summer heat arrives.

Summer (June–August): Hurricane Preparation

Complete any necessary repairs before hurricane season peaks. Secure loose flashing, reinforce vulnerable areas, trim overhanging branches that could become projectiles, and verify that your roof's wind resistance meets current code requirements for Chatham County.

Fall (September–November): Post-Storm Review

After the peak of hurricane season, inspect for wind damage, water intrusion, and debris impact. Fall is the best time for roof replacement projects in Savannah — temperatures are moderate, rainfall decreases, and contractors have greater availability before the holiday season.

Winter (December–February): Moisture Management

Savannah winters are mild but can bring freezing rain and occasional ice. Ensure gutters are clear, downspouts are directing water away from the foundation, and attic insulation is preventing heat loss that could cause condensation issues. Winter is also an excellent time to plan and budget for spring projects.

Choosing Materials for Savannah's Climate

The data points to clear material advantages for Coastal Georgia. Homeowners in Savannah, Pooler, Richmond Hill, and Tybee Island should prioritize materials that resist UV degradation, handle thermal cycling, shed moisture effectively, and meet wind-resistance requirements for our coastal wind zone.

• Best overall: Standing-seam metal roofing — reflects UV and heat, handles thermal cycling without fastener issues, sheds water instantly, rated for 140+ mph winds.
• Best shingle option: SBS-modified architectural shingles with algae resistance — flexible, UV-resistant, 130 mph wind rating with proper installation.
• Budget-conscious: Premium architectural shingles with 6-nail patterns and sealed deck underlayment — maximizes performance within a traditional shingle budget.